Investigation of "rapid" methods of sterility testing were initiated this year. Preliminary studies with two organisms have examined the length of time necessary to detect contamination using one rapid method and one compendial method. The advantages observed in the pilot study have encouraged a more comprehensive study. In most cases, contamination was observed earlier with the rapid method than the direct sterility test. However, with only three months of work, this data is considered preliminary. For biological products that are required to be sterile, testing mandated by the Code of Federal Regulations requires a 14 day incubation period, with observations based on visual examination, to conclude that the product is free from extraneous bacterial contamination. A group of newly emerging "rapid" methods suggests that such bacterial contamination can be detected in less than 14 days by other methods. Some of these methods employ devices that detect carbon dioxide production. Other methods involve optical systems that detect bioluminescence from ATP metabolism of the contaminants. The Microstar system, made by Millipore Corporation, is an example of the latter technology, and was selected for evaluation based on the laboratory's current use of existing Millipore Steritest equipment and supplies. This project will be exapnded to compare the detection of a variety of organisms at different contamination levels, using the rapid methods combined with traditonal sterility techniques, modifications of such techniques, and adaptations of bioburden testing. Challenges with organisms in media will be expanded to challenges in products with parallel compendial testing. Collaboration with other laboratories is anticipated, and development of a validation protocol will provide the information necessary to accept or reject this method as an acceptable alternative to compendial testing. Realizing the broad scope of current sterility testing, in the variety of products tested and the scope of possible contamination, the advantages of a method that could shorten testing time while retaining the ability to detect a variety of contaminants would be valuable. In-process testing could also be accelerated, allowing a company to recognize a problem earlier. Validation of such a system would favorably impact cell products that must be infused into patients prior to the completion of the 14 day incubation period now required.